Water-tube boiler



'2 Sheets-Sheet 1;

(No Model.)

J. JOHNSTON. WATER TUBE BOILER. No. 454,215.

Patented June 16,1891.

2 Shets-Sheet 2.

(No Model.)

Patented'June 16 1891.

J. B'. JOHNSTON. WATER TUBE BOILER.

m: NORRIS PETERS cm, mom-u'mm, wAsnmr-fan, n. c.

UNITED STATES PATENT OFFICE.

JAMES B. JOHNSTON, OF MUSKEGON, MICHIGAN.

WATER-TUBE BOILER.

SPECIFICATION formingpart of Letters Patent No. 454,215, dated June 16,1891.

Application filed January 31, 1891. Serial No. 379,811. (No model.)

To all whom, it may concern.-

Be it known that I, JAMES B. JOHNSTON, a citizen of the United States,residing atfMuskegon, in the county of Muskegon and State of Michigan,have invented certain new and useful Improvements in Steam-Boilers, ofwhich the following is a full, clear, and exact description, such aswill enable others skilled in the art to which it appertains to make anduse the same, reference being had to the accompanying drawings, and tothe letters of reference marked thereon, which form a part of thisspecification.

This invention relates to improvements in steam-boilers of that classcommonly known as water-tube boilers, and has for its object theconstruction of a boiler in which water is first fed into a water-tankor steamdrum in such a manner as to be spread over as much space aspossible, so that the cold water will be gradually introduced into thehot water, and of a generating-chamber and tubes to which water can befed from the tank situated above the same, so as to enter a compartmentof the generating-chamber and be conducted therefrom by interior pipesinto exterior pipes, where it is exposed to the action of the heat inthe combustion-chamber of the furnace, and when after being so exposedand converted into steam be conducted by the said exterior pipes toanother compartment of the generating chamber, and thence be conductedby suitable connections to the water-tank or steam-drum, therebysecuring a rapid circulation, which will insure a rapid generation ofsteam.

The invention consists of a furnace of suitable construction adapted tothe purpose, a generating-chamber divided into two compartments by asectional partition, the exterior water-tubes emptying into the inner ofthe said compartments, and interior tubes leading from the outer of thesaid compartments and passing through the inner one into the exteriortube and extending into the same nearly its entire length.

The invention further consists in the novel construction, combination,and arrangement of parts, such as will be hereinafter more fullydescribed, pointed out in the appended claim, and illustrated in theaccompanying drawings.

In the accompanying drawings, in which similar letters of referencedesignate corresponding parts, Figure 1 is a longitudinal verticalsection of a boiler embodying the invention. Fig. 2 is a transversevertical section on the line m at of Fig. 1. Fig. Sis a longitudinalsection through the exterior and interior tubes, showing them in theirrelative positions and the means whereby they are so retained, and italso shows the device for closing the rear end of the exterior tube.Fig. 4is a front elevation of the partition which divides thegenerating-chamber into two compartments. Fig. 5 is a transversevertical section on the line a z of Fig. 4. Fig. 6 is a transversehorizontal section on the line '0 o of the same figure.

Referring to the drawings, A represents a furnace of any suitableconstruction adapted to the purpose, consisting of the side walls B B,the front and back walls 0 and O, respectively, and the arched top D. Inthe front lower part of the furnace is the fire-box E, and beneath it isthe ash-pit E. They are separated from the combustion-chamber E by thebridge E.

E is an arch supporting the rear end of the water-tank T and separatingthe upper part of the combustion-chamber from the uptake E serving todeflect the products of combus-.

tion which may have arisen in the front part of the chamber downward, sothat they may again come in contact with the water-tubes and the heat beutilized to the greatest extent.

To the sides of the generating-chamber are attached the supports a a,which rest upon projections of the side walls and serve to sustain thechamber in its proper position. In the back plate I) of thegenerating-chamber are secured in the ordinary manner the exteriorwater-tubes G G, the rear ends of which are supported in the plate G,seated in an 9 tion tends to give a more rapid circulation,

as the heated water or steam will always pass out the upper ends and thecolder water will enter the lower ends, a regular current upward throughthe tubes always existing.

' In the front end of the generating-chamber is a man-hole provided witha suitable cover F which allows ready access to the chamber.Communication from the exterior of the furnace to the said man-hole ishad by means of the door H.

In the upper part of the furnace,having its rear end resting uponthearch E and its front end in the wall 0, is the water-tank orsteamdruln T, connected with the generating-chamber by the pipe T.Access to the interior of the tank is had through the man-hole T ater issupplied to the tank by the supplypipe T which enters the front end ofthe same and extends nearly its entire length and rests its rear end ona support 1. This pipe is perforated its whole lengththat is, as much ofit as is in the tankso as to distribute the water over as much space aspossible, and thereby gradually introduce the cold water into the hotwater. The tank is partly divided into two compartments by thesemicircular partition 75*, vertically placed over the opening of thepipe T.

The generating-chamber is divided into two compartments f and f by thevertical partition K, which is connected with the partition is of thetank by the plate 7& placed within the pipe T. The general outline ofthese partitions and the connecting-plate is such that the edges willset closely against the adjacent walls. The partition K is formed ofsections is of such size as may be readily removed through the man-holeF. It maybe divided into only three pieces, as is shown in Fig. 2; butfive, as shown in Figs. 4, 5, and 6, is the preferred number.Connections between the several sections of the partitions K and 75 andthe plate k is made by overlapping the adjacent edges and passingthrough them the bolts s s, which have perforated ends, in which areseated the keys 3 s. The partition K also forms a support for the frontends of the interior water-tubes G G which will be described farther on.These tubes serve to mutually support the partition in its uprightposition. It might be well to state here that the joints between thesections of the lower partition and between the partitions and the sidesof the tank and chamber need not be water-tight, as the latter onlyserve to separate two currents of water and not to divide the water intoseparate bodies.

The object of having the partition K in sections is to allow its removalwhenever it is desired to have access to the front ends of the tubes G,for if it were in one piece it could not be removed and the spacebetween it and the sheet I) would be too narrow to allow a readymanipulation of tools therein.

G G represent water-tubes, which have their front ends secured in theplate b, which forms the back of the generating-chamber F, and open intothe compartment f. Their rear ends are secured in the plate G, seated inan opening formed in the rear wall C, which is covered by the door 0 Themeans used to secure the front ends of the tubes in the plate I) arethose which are ordinarily used. As it is often necessary to have accessto the rear ends of, the tubes for examining their interior and forcleaning, a different means is adopted for securing the said rear endsin place and also for closing the opening at the same time. Before thetube is placed in position a collar M, having its outer peripherythreaded, is placed upon it, and then the tube is placed in position andsoured to the plate I) at its forward end. A wedge-shaped plug on and arubber gasket m are placed in the flared opening in the lower end of thetube. Acap N, havingits interior periphery threaded, is placed over theopening and is screwed to the collar M, thereby securing the plug inplace and securing the tube against any tendency that it may have to bedrawn into the furnace.

G G are smaller water-tubes carried for nearly their entire lengthwithin the tubes G G, their ends reaching almost to the ends of theinclosing tubes at the rear and are supported therein by the lugs Z Z.The front ends of these tubes pass through the compartment f and areseated in the partition K and open into the compartment f. The pins19 1) hold them in their proper relative positions.

The operation of the device is as follows:

. Fire having been started in the fire-box, the

products of combustion on their way to the uptake will pass around thetubes G G, and as these tubes are the first ones heated the water in theannular space formed between the interior and the exterior tubes willconsequently be heated first. The steam there created will rise in theexterior tube and flow into the chamber f, thence through theconnecting-pipe into the tank or steam-drum T,

from which it can be taken by means of the outlet U. As the water leavesthe tubes G G, the water in the tubes G G must flow from the lower endsof the latter into the former and be heated in turn. This will cause aninflowing current into the compartmentf from the tank and an outflowingcurrent from the compartment f into the tank. These currents will beseparated from each other by the partitions K and k and theconnecting-plate so that they cannot mingle and interfere with eachothers movements and thereby cause a very rapid circulation and a quickgeneration of steam.

Having thus described my invention, what I claim,and desire to secure byLetters Patent, is

In a steam-boiler, the combination of the generating-chamber, thesectional partition separating the said chamber into two comleading fromthe same and opening into the inner of the compartments of thegeneratingchamber, substantially as described.

In testimony whereof I affix mysignature in presence of two witnesses.

JAMES B. JOHNSTON.

Witnesses:

F. H. SoHoTT, W. H. BARNES.

